Concise synthesis of a fused energetic pyrazolotriazine with good performance

Abstract

Ring-fused heterocycles are a promising direction for insensitive high-energy materials (IHEMs). Besides, the scalable synthesis of IHEMs is a favourable factor for practical applications. A new fused energetic pyrazolotriazine, 4-amino-3,8-dinitropyrazolo[5,1-c][1,2,4]triazine (GD-1), was synthesized via the construction of a pyrazolotriazine skeleton followed by nitration starting from the cheap and commercially available 5-aminopyrazole. GD-1 crystallizes as GD-1·2H₂O (monoclinic) or GD-1·CH₃OH (orthorhombic) when crystallized in acetone or methanol. GD-1 with a monoclinic crystal system has a high density (ρ = 1.83 g cm⁻³), good detonation performances (V_D = 8895 m s⁻¹, P = 35.4 GPa), good thermal stability (T_p = 306 °C) and low sensitivities (IS > 60 J, FS > 360 N). The good performances as well as the readily scalable synthesis make GD-1 a potential IHEM.